X-Git-Url: https://git.madduck.net/etc/vim.git/blobdiff_plain/bd9d52b52d58df60bffe164309a48cb61ac8d3b7..7af3abd38392588ac737bae09f6b15d80fe344b1:/src/black/trans.py?ds=sidebyside diff --git a/src/black/trans.py b/src/black/trans.py index cb41c1b..74d052f 100644 --- a/src/black/trans.py +++ b/src/black/trans.py @@ -24,9 +24,9 @@ from typing import ( import sys if sys.version_info < (3, 8): - from typing_extensions import Final + from typing_extensions import Literal, Final else: - from typing import Final + from typing import Literal, Final from mypy_extensions import trait @@ -71,6 +71,88 @@ def TErr(err_msg: str) -> Err[CannotTransform]: return Err(cant_transform) +def hug_power_op(line: Line, features: Collection[Feature]) -> Iterator[Line]: + """A transformer which normalizes spacing around power operators.""" + + # Performance optimization to avoid unnecessary Leaf clones and other ops. + for leaf in line.leaves: + if leaf.type == token.DOUBLESTAR: + break + else: + raise CannotTransform("No doublestar token was found in the line.") + + def is_simple_lookup(index: int, step: Literal[1, -1]) -> bool: + # Brackets and parentheses indicate calls, subscripts, etc. ... + # basically stuff that doesn't count as "simple". Only a NAME lookup + # or dotted lookup (eg. NAME.NAME) is OK. + if step == -1: + disallowed = {token.RPAR, token.RSQB} + else: + disallowed = {token.LPAR, token.LSQB} + + while 0 <= index < len(line.leaves): + current = line.leaves[index] + if current.type in disallowed: + return False + if current.type not in {token.NAME, token.DOT} or current.value == "for": + # If the current token isn't disallowed, we'll assume this is simple as + # only the disallowed tokens are semantically attached to this lookup + # expression we're checking. Also, stop early if we hit the 'for' bit + # of a comprehension. + return True + + index += step + + return True + + def is_simple_operand(index: int, kind: Literal["base", "exponent"]) -> bool: + # An operand is considered "simple" if's a NAME, a numeric CONSTANT, a simple + # lookup (see above), with or without a preceding unary operator. + start = line.leaves[index] + if start.type in {token.NAME, token.NUMBER}: + return is_simple_lookup(index, step=(1 if kind == "exponent" else -1)) + + if start.type in {token.PLUS, token.MINUS, token.TILDE}: + if line.leaves[index + 1].type in {token.NAME, token.NUMBER}: + # step is always one as bases with a preceding unary op will be checked + # for simplicity starting from the next token (so it'll hit the check + # above). + return is_simple_lookup(index + 1, step=1) + + return False + + leaves: List[Leaf] = [] + should_hug = False + for idx, leaf in enumerate(line.leaves): + new_leaf = leaf.clone() + if should_hug: + new_leaf.prefix = "" + should_hug = False + + should_hug = ( + (0 < idx < len(line.leaves) - 1) + and leaf.type == token.DOUBLESTAR + and is_simple_operand(idx - 1, kind="base") + and line.leaves[idx - 1].value != "lambda" + and is_simple_operand(idx + 1, kind="exponent") + ) + if should_hug: + new_leaf.prefix = "" + + leaves.append(new_leaf) + + yield Line( + mode=line.mode, + depth=line.depth, + leaves=leaves, + comments=line.comments, + bracket_tracker=line.bracket_tracker, + inside_brackets=line.inside_brackets, + should_split_rhs=line.should_split_rhs, + magic_trailing_comma=line.magic_trailing_comma, + ) + + class StringTransformer(ABC): """ An implementation of the Transformer protocol that relies on its